Three more sewage treatment plants would come up across the city to treat sewage generated from the ever-expanding city.

At present, Chennai has a capacity to treat a total of 558 million litres of sewage being generated daily in 11 units set up at six locations. Work is on to set up sewage treatment plants with a capacity to treat 228 mld in four more spots.

The three new STPs would come up in Villivakkam (135 mld), Sholinganallur (100 mld) and Navalur (6 mld). Moving the demands for grants for the Municipal Administration and Water Supply department, Minister K.P. Munusamy said that five STPs generate power from biogas to meet their requirements. In the past seven years, about 1.424 megawatt of electricity was saved and emission of nearly 3.73 lakh tonnes of carbon dioxide was reduced.

He also highlighted the sewerage infrastructure schemes being taken up in various merged areas with the assistance from Jawaharlal Nehru National Urban Renewal Mission and Tamil Nadu Urban Development Project.

While water supply has started from the second desalination plant at Nemmeli, the water agency has appointed Aecom India Private Limited along with GHD Pty Limited, Australia, and Watek Engineering Corporation, USA, to prepare the project report on the feasibility of a desalination plant at Pattipulam, which is four kilometres away from the Nemmeli plant. Unlike the existing two plants with a capacity to treat 100 million litres of sea water a day, the proposed plant would treat 200 mld, which could be further expanded to 400 mld.

The water agency is also taking measures to extend the water supply to Tambaram, Pallavaram and Pammal by laying a 22-km pipeline from Poonamallee bypass junction to Tambaram. Work sanctioned under Infrastructure and Amenities Fund will start soon.

Meanwhile, Metrowater is set to complete the project to lay a second pipeline running to a length of 6.5 km from Chembarambakkam water treatment plant to the Poonamallee bypass junction by July next year.

This would help transmit the entire 530 mld of drinking water that the Chembarambakkam plant is capable of treating to residents.